Question: Who is the writer of On Liberty who's birthday is May 20, 1806?
Paraphrase: Who is the creator of On Liberty who's birthday is May 20, 1806?
SPARQL (Wikidata): SELECT ?answer WHERE { wd:Q1055881 wdt:P50 ?answer . ?answer wdt:P569 ?x FILTER(contains(YEAR(?x),'1806'))}
Answer: John Stuart Mill